This invention relates generally to immunochemistry and, more particularly, to a method of determining the occurrence or non-occurrence of an immunological reaction between antigens and antibodies.
Blood group serology requires the determination of blood cell compatibility between donor and patient before a transfusion or organ transplant. Blood cell compatibility is determined by the non-occurrence of an immunological reaction between antibodies contained in the blood serum of a patient and antigens present on blood cells from a donor. A patient whose red blood cells are type A (i.e., have "A" antigens on the red cells) will have Anti-B antibodies in his or her serum. Thus, if such a person is given type B blood, an immunological reaction will occur with possible serious clinical consequences.
Blood group serology has most commonly been carried out in liquid phase where the two blood types are interacted and observed for agglutination which indicates that an immunological reaction has occurred. Liquid phase blood group typing is time consuming, somewhat cumbersome, greatly dependent upon the skill of the technician and, to some degree, not sensitive enough to detect all antibodies. A considerable advance in the art of blood group serology is represented by U.S. Pat. No. 4,275,053 to Rosenfield, issued June 23, 1981. This patent is directed to a procedure for conducting blood group serology in solid phase. The disadvantages of liquid phase hemagglutination tests as well as the advantages of working in the solid phase are discussed in detail in the referenced patent, the disclosure of which is specifically incorporated by reference into the subject application. Briefly stated, the Rosenfield patent is directed to a procedure whereby a monolayer of cells of known antigenic composition is irreversibly bound to the walls of a plastic tube. The tube is then contacted with a solution of unknown antibodies which, if they are specific for the antigens of the attached cells, will undergo an immune reaction. The cell layer is lysed and washed to remove hemoglobin. A second solution of known antigen-carrying cells is then applied to the solid matrix in several steps and the extent of the antibody-antigen reaction is measured by the degree to which the second monolayer of cells is immunologically adhered to the antibody layer. The results may be evaluated utilizing densitometric techniques.
It has also been previously demonstrated that viral antibodies can be directly attached to a solid matrix for radio or enzyme linked immunoassays. The technique which has been employed is particularly suitable to non-blood group antibodies and antigens because specific immunoglobulins can be isolated and the investigator is concerned only with a specific reaction. This technology has heretofore not been applied to blood group serology. Furthermore, non-blood group immunological reactions have heretofore relied upon elaborate and time-consuming multiple step processes to attach some type of label, such as radioisotopes, enzymes or fluorophores, to antigens and antibodies in order to measure their participation in an immunological reaction.